Slotting machine



Nov. 3, 1953 c. F. JONES 2,657,615

SLOTTING MACHINE Filed July 21, 1950 4 Sheets-Sheet l INVENTOR. Cerggzdlifones, BY

09% kw w;

Nov. 3, 1953 c. F. JONES 2,657,615

SLOTTING MACHINE Filed July 21, 1950 4 Sheets-Sheet 2 QINVENTOR. Cerr zyzI/Zi/Znea BY wk, M. 74 W C. F. JONES SLOTTING MACHINE Nov. 3, 1953 4 Sheets-Sheet 3 Filed July 21 1950 'INVENTOR. Cer aywjfifanea v BY %W.%, mfw

Nov. 3, 1953 c. F. JONES 2,657,615

SLOTTING MACHINE Filed July 21, 1950 4 Sheets-Sheet 4 &\

A H N N m m g $15 g Q I o g m 1 ZS if I INVENTOR.

Cemzgw lfanes, BY

Patented Nov. 3, 1953 SLOTTING MACHINE Cernyw F. Jones, Economy, Ind., assignor to Perfeet Circle Gorporation, Hagerstown, Ind., a corporation of Indiana Application July 21, 1950, Serial No. 175,267

20 Claims.

The invention relates generally to machines for cutting slots and more particularly to a machine for cuttin slots in cylindrical articles such as piston rings for internal combustion engines or the like.

One well-known form of piston ring comprises a ring member substantially rectangular in radial cross section with a circumferentially extending groove in the outer periphery and with a series of circumferentially spaced radial slots extending through the ring. Each slot is relatively narrow in a direction axially of the ring but usually is elongated circumferentially. Such slots are ordinarily formed by means of a circular cutter positioned in the midplane of the ring and fed radially inward of the ring from the outer periphery thereof. Because a cutter of relatively small diameter is necessary to cut slots of the desired size, the circumferential ends of each slot are of arcuate shape, curving toward each other inwardly of the ring. Such a slot is relatively long circumferentially at the outer periphery of the ring and is necessarily substantially shorter at the inner periphery, and if the slots are to have sufficient opening at the inner periphery, they will be quite long at the outer periphery and therefore relatively few slots may be cut in the ring.

The general object of the invention is to provide a slotting machine capable of cutting slots with ends approaching a position parallel to each other or nearly so, rather than the arcuate form of ends obtained by the ordinary circular cutter.

Another object is to provide a slotting machine for cutting slots in cylindrical members such as piston rings, with the ends of the slots of such shape that the angular extent of each slot at the outer periphery is substantially the same as the inner periphery.

A further object is to provide a slotting machine for cutting slots in cylindrical members such as piston rings, by means of which shorter slots with sufficient opening at the inner periphery of the ring may be obtained than has heretofore been possible with previous forms of slotting machines.

Still another object is to provide a slotting machine of the foregoing character, in which a cutter having an arcuate series of teeth generally similar to a portion of an ordinary milling cutter is used but with the teeth adapted to be arranged on a much smaller radius than in the case of the conventional cutter, and which includes means for imparting a novel cutting movement to the cutter.

A still further object is to provide a novel slotting machine of the foregoin character, by which a uniformly spaced series of slots may be cut in the Work piece and which may accommodate work pieces of different diameters and with a different number of slots to be out in them.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a fragmentary plan view of a piston ring of the type herein contemplated, and showing the form of slots as heretofore made.

Fig. 2 is a view similar to Fig. l but showing the form of slots capable of being made by a slotting machine embodying the features of the invention.

Fig. 3 is a diagrammatic view illustrating the manner in which slots are cut by the present slotting machine.

Fig. 4 is an enlarged elevational view of a cut ter employed in the present slotting machine.

Fig. 5 is a side elevational view of the slotting machine. 1

Fig. 6 is a horizontal sectional view taken substantially on the line 6-6 of Fig. 5.

Fig. 7 is a fragmentary vertical sectional view taken substantially on the line 'l'! of Fig. 5.

Fig. 8 is a fragmentary vertical. sectional view taken substantially on the line 88 of Fig. 5.

Fig. 9' is a fragmentary sectional view taken substantially on the line 9--9 of Fig. 5.

As heretofore mentioned, the slotting of piston rings of the type disclosed has usually been performed by means of a circular cutter positioned in the mid-plane of the ring and fed radially inward of the ring starting at the outer periphery thereof, the cut terminating when the cutter has broken through the inner periphery of thering to the desired extent. A ring of this type is shown in Fig. 1, and it will be noted that such slotting will leave intervening wall portions 20 between the ends of slots 29 with the cylinderengaging rail portions 22 left on opposite sides of each slot. The ends of the slots defining the intervening wall portions 20 are arcuate in form,

that relatively few slots of this character may be cut in a ring. This tends to weaken the ring since the rail portions 22 are supported by relatively few intervening wall portions 26 and the ring, if overloaded, will tend to break through the wall portions 22 at one of the slots. Moreover, because of the excessive length of the slots, there is a. tendency for the ring to-fiatteir initherail portions at the slots when the ring is confined in the cylinder because of the length of such rail portion and because the bending of the rin is confined to relatively few such rail portions.

A slotting machine embodying the features of the invention is capable of cutting slots having ends which approach parallelism, or at least positions radial of the ring, so, that theangular extent of the slot at the outer periphery is not substantially greater than the angular extent of the slot at the inner periphery. In Fig. 2, there is illustrated: a. ring of this type, in which. there is shown an intervening wall portion 24 between. apair' of slotsv 25. Itwill be. noted: that in this. form. of slotting, the. ends. of the slots; indicated at. 25, while somewhat arcuate, are placed. closer tma radius of the ring-than; is shownin the form illustrtaed in. Fig. 1', so that the opening of each slot at: the outerperiphery-is OnlysIightIy-greaterthan the. opening of the: slot at. the inner periphery. This provides several advantagessince; tor a given amount of: opening at the inner pe riphery; eachslot may be substantially shorter" than has heretoforebeen possible, and. an increased. number. of slots. may be placed in any ring. Furthermore, therail portions at: the upper and lower sides of each slot are shorter. This results in a stronger ring with the rail portions less likely to breakand: increases the spring load of the ring'. The ring as a whole is thus stiffer to resist bending. Moreover, wit-ht the increasednumbcr of slots in a.- ring of a given size, the

bending of the-rails at the sides of each.- slot will.

be decreased so that less distortion and flatness occur in the ring as a whole.

In Fig; 3 of the drawings, I have illustrated diagrammatically howslots of the character illustrated at 25 in Fig. 2 are cut, the cutter employed for this purpose being illustrated in. Fig. 4:. The cutter, indicated generally at 29,. 1510f elongated form and at one end thereof is a series of teeth. 30. arranged in an are about an axis, indicated at 3t, located adjacent that end of the: cutter. The teeth are similar to those; of: a conventional cutter but, since noarbor extends through the cutter on the axis 34, the radius. of the teeth. from this axis may be. much: smaller than in the. case of the conventional cutter. The.- teeth, are shown as. being adapted for cutting when the cutter is rotatively moved about the axis. 3.! inonly one direction, in this instance av clockwise direction, as is apparent from the. shape. of the teeth. To accomplish the cutting action with this form of cutter, the machine is constructed to provide both. rotative or rocking movement of the cutter about the axis 3|. and. simultaneously therewith, to reciprocate the cuter longitudinally, that is, in a direction perpendicular to the axis 3|. To accomplish such. movement, the cutter is supported in such a manner that it may be rocked about its axis 3| and at the same time reciprocated, the cutter suport being adapted to be actuated in this manner by arotatably driven. combined camand crank means.

To accomplish such cutting movement the motion but, through the. same angle.

cent its other end, which is mounted and clamped on a pin 33 (see Figs. 5 and 6) carried on an oifset portion 34 of a tool post 35. The offset portion 34 is formed on one end of the tool post 35, and on the opposite end thereof is mounted a roller 36 as well as a lever 31. The combined cam and crank means cooperates with the roller 36.: and lever 3.1 to. impart the desired; movement to the cutter. Thus, there isprovided a cam member or disk 40 having a peripheral cam surface adapted to engage the roller 38 to impart reciprocating movement to the tool post and thus to the cutting tool 29. The cam member 4fli-al'so has:a crank pin 4| mounted on one face thereof and cooperating with the lever 31 to rock the tool post 3 5. The tool post 35 is mounted so thatsuch rocking movement is on the axis 3| about which the teeth 30 are formed.

Referring again to Fig. 3, where the cutting action is diagrammatically illustrated, it will be noted: that upon rotation of the cam disk 40' in a counterclockwise direction, as illustrated. in; Fig; 3,. the crank pin, 41 and the lever 31 cause the. latter tov rock the tool postand cQnsequently the cutter in a clockwise direction while the cam isv moving through the angle. indicated at. A. This rocking movement obviously causes, the teeth, of the cutter. tch swing in a clockwis die rection and to effect, a cutting action onthe ring. indicated at 42 in Fig. 3:. During, the. remainder" of each revolution of the cam disk 40' and the. crank pin 41-, that is, while the crank. disk is moving through the angle;- indicated by B,. the cutter will be rocked in the opposite di- Thus, thecutting tool is first. rocked, through an angle indicated at C. in a. clockwise direction to perform a cutting: stroke and then: is; reversely rocked in a counterclockwise direction through the samev angle C on a return stroke. Inthe illustrated, embodiment. of the invention, the 6111* mensionsv of the variousparts are suchthat the angle A is- 120 and the: angle B is. consequently- 240, and the angle C", representing the angular rocking; movement of the; cutter, is

Simultaneously with such rocking movement of the cutter, the cam. surface on the cam. member 40, cooperating with the roller 36 on the tool post, produces a reciprocating movement or the cutter bodily toward. and. from the: work. Such. reciprocating, movement is relatively slight. and preferably only a few thousandths of an inch. This; reciprocating movement, or course, occurs. at the. same time that the cutter is being rocked, since the reciprocating movement results from. the shape ofthe cam surface on the cam 40, and the; crank pin-.41. is carried by this same cam member. The cam surface is arranged so that the cutter is moved from a more or less; central. position, indicated by the line 43, toward the work; to a position indicated by the line 44, and. thence back to the; central position 43, while the cutting teeth are rocked in a clockwise direction topertorm a cutting stroke. Thus, the cutting teeth will clear the work at the end of the cutting stroke. During the counterclockwise movement of the cutter, the cam member 4!! eifects movement of the cutter from the central position, indicated at 13, away from the work toa maximum withdrawn position, indicated by the line 45, and thence back to the central position 43 so that during the return stroke of the cutter, when it is moving in a counterclockwise direction, the teeth are entirely cutter 25 is provided with an aperture 32 adja- 15- clear of any cu a ment with the work.

To insure further clearance of the teeth at the end of the cutting stroke, the angular spacing of the teeth is less than the angular movement during the cutting stroke so that there is an overlap of the path of travel of adjacent teeth, as indicated by the angle D. In the preferred construction, where the cutter is moved through an angle of 60 during the cutting stroke, the teeth in the cutter are preferably spaced substantially 45 apart so that there is an overlap of 15, as indicated by the angle D. The clearance effected thereby is indicated in Fig. 3 of the drawing at 46 and the overlap insures having the cutting point of each tooth clear the cut made by the tooth ahead of it. To facilitate an understanding of the movement of the cutter, the teeth of the cutter have been numbered, and their initial position is shown in dotted lines and their final position in full lines.

From the foregoing, it will be apparent that the cutting action is effected by causing the cutter to rock in a clockwise direction about the axis of the teeth and at the same time move inwardly of the work and then outwardly so that the teeth dig into the work to effect a cut and are moved clear thereof before being returned to their initial position for making a second cut. The machine also includes means for gradually feeding the cutter into the work,

as will hereinafter be described, so that cuts of any desired depth may be eifected. The reciprocation of the cutter heretofore referred to is effected in the preferred embodiment of the machine by a swinging movement rather than strict linear reciprocation, as hereinafter described. However, because such reciprocation is only a few thousandths of an inch in extent and the radius of swinging is relatively great, any curvature due to such swinging movement is entirely negligible and the movement thus may be considered reciprocatory. In the case of cutting slots in a piston ring, the feeding movement as hereinafter described is carried on to a suflicient extent to cause the teeth to break through the inner periphery of the ring and form a slot of the desired circumferential length in the ring. The invention, however, is obviously not limited to cutting slots in piston rings but may be used for cutting slots in other forms of work pieces.

The machine for performing such cutting action is illustrated in Figs. 6 to 9, inclusive, and has a frame structure including a main frame preferably comprising a base 53 having flange portions 5| at two of its sides, by which it may be bolted to a bench or the like. Mounted on the base is a main frame of box-like construction and comprising a front wall 52 and a rear wall 53 of relatively heavy construction. The walls 52 and 53 are connected at their ends by end walls 54 and at their upper edges by a top wall 55. The walls 52 and 53 are preferably held in spaced relation to each other by bolts 58 threaded into spacing members 59 located at the four corners of the Walls. The work piece, which is here illustrated in the form of a piston ring 55, is carried on a work support, here indicated generally at 51, mounted on the front wall 52. The work support 51 comprises a slide 60 mounted for linear adjustment on the front face of the front wall 52 and adapted to be clamped thereto by a clamping bolt 6! (see Figs. 5 and 6) threaded into the slide BI] and extending rearwardly through a slot 62 in the front wall and a slot 63 in the rear wall. Mounted on the clamping bolt at the rear face of the front wall 52 is a bridge piece 64 adapted to be clamped against such rear face by an elongated sleeve 65 mounted on the clamping bolt and secured thereon by a nut 66 on the rear end of the bolt. The clamping bolt 6| and sleeve 65 are of elongated form, so that they may extend to the rear of the rear wall 53, and the nut 65 is thus readily accessible for tightening when the slide 60 is moved to an adjusted position. To effect linear adjustment of the slide 60, a hand screw 6'! is rotatably mounted in the right-hand end thereof and is threaded in a nut 10 bolted to the right-hand edge of the front wall 52. Thus, when the nut 66 on the clamping bolt 6! is released, the hand screw may be turned to adjust the slide 60 longitudinally.

The slide 60, at its opposite end, carries a post H, on which an indexing disk 12 is mounted. The work piece 56 is adapted to be clamped against the front face of the indexing disk 12 by means of a clamping disk 13 adapted to be moved into clamping engagement with the work piece 56 by a nut 18 threaded on a sleeve 14 extending forwardly from the indexing disk 12 about the post H. Thus, by tightening the nut 18, the work piece 56 may be tightly clamped between the indexing disk 12 and the clamping disk 13.

Since it is desired to be able to cut slots in the work piece at uniformly spaced intervals about the circumference of the work piece, the indexing disk 12 is provided with a series of peripheral notches 15 adapted to cooperate with a tooth 16 formed on an indexing lever 1'! carried on the slide 60. When the tooth 16 is seated in one of the notches 15 the indexing disk is adapted to be clamped against the slide 60 to hold it in fixed position. For this purpose, a nut provided with a handle 19 is threaded on the front end of the post H and bears against the sleeve I4 integral with the indexing disk 12 to force the indexing disk into clamping engagement with the slide 60.

The indexing lever 11 is pivotally supported on the slide 60 by means of a pin 8|, and a tor.- sion spring 82 is mounted on the pin 8| and bears at one end against the slide 60 and at its other end against the lever 11, tending to swing the lever toward the indexing disk and thus hold the tooth I6 in one of the notches-15. When it is desired to cut slots in work pieces of different diameters, indexing disks and clamping disks of different sizes are employed, both of thesemembers preferably being substantially equal in diameter to the work piece. When different diameters of indexing disks are employed, the indexing lever 11 will require adjustment. For this purpose, the pin 8! pivotally supporting the indexing lever 11 extends through a slot 83 formed in the slide 60 and extending longitudinallythereof, so that the pivotal support for the indexing lever may be adjusted to permit the indexing lever to assume a suitable position relative to the indexing disk.

The tool post 35, the movement of which has heretofore been described in connection with the cutting action of the tool 29, is consrtucted and supported as shown in Figs. 6 and '7. Thus, the roller 35 is carried on the inner end of the tool post 35 by means of an anti-friction bearing 84,

portion 34, by anti-friction bearing-s -81 mounted in :an arm 30. The arm 90 is mounted for swinging movement on a pivotal support .9! with antifriction bearings '92 interposed between the pivot-al support 91 and the arm 89. The swinging movement of the arm 90 on its pivotal support thus provides for the reciprocatory movement of the cutter toward and from the work while the cutter is being rocked by the'crank pin M and the rocking lever 31. The roller .35 is :held

in engagement with the periphery of the cam I member 43 by means which is herein illustrated as comprising a spring 93 (see big. '6) mounted in a bracket .94.

As heretofore mentioned, the machine includes means for feeding the cutter into the work and for withdrawing it therefrom at the completion of a cutting operation. Such feed is, of course, superimposed on the reciprocatory and rocking movement of the cutter. The feeding movement is accomplished by providing a gear box, inclicated generally at I and constituting a part of the frame structure, which is pivotally -mount ed in the main frame of the machine, so that swinging movement of the gear box will feed the cutter into the work. The gear box H30 oomprises a front wall IOI and a rear wall I [62 which are held in spaced relation to each other by various shafts mounted therein and by bolts -.I I13 (see Figs. and 6) extending through the front and rear walls NH and 1-32 :and threaded into a spacing member I M, the latter preferably being mounted at one corner of the front and rear walls 1M and 32.. Since the feeding movement is superimposed .on the reciprocatory movement of the cutter, provided by the arm 90, the pivotal support SI for the arm =90 is carried on the front wall .IIlI of the gearbox, as shown in Fig. "7, and is rigidly secured thereto as by a bolt I415, Also, the bracket 94 which supports the spring 93 is carried on the front wall of the gear box, as shown in Fig. .6, so that the pressure exerted by the spring .93 to hold the .roller 35 against the periphery of the cam member 40 is .substam tially uniform throughout the feeding movement.

The cam member 40 .is adapted to be power driven and, to this end, is rigidly mounted in front of the front wall I!!! of the gear box on a shaft I05 journaled in both the front and rear Walls IIJI and I02. The .shaft I05 also has rigidly secured thereto a pinion I01 located within the gear box and meshing with a relatively large idler gear H0. The idler gear III] is keyed to a shaft III (see Figs. 5 and 9) journaled in the gear .box walls. The idler gear III] also meshes with a drive pinion H2 keyed to a drive shaft H3. The drive shaft H3 extends rearwardly through the rear wall I 02 of the gear box as well as the rear wall 53 of the main frame and is adapted, at its rear end, indicated at HII, to receive a driving member, such as a pulley (not shown), adapted to be connected to a source of power.

The axis of the drive shaft H3 also is the axis about which the gear box I00 swings to effect feeding movement of the cutter. To this end,

the drive shaft I I3, at its front end, is ,journaied in a sleeve H5 '(see Fig. 9) which is rigidly secured to the front wall I.IJI of the gear box as by bolts H6 and which is journaled by means of an anti-friction hearing I I1 a flange member I rigidly secured to the front wal152 of the main frame as by bolts I21. The rear end of the drive shaft H3 is journalecl in a sleeve J22 rigidly secured to the rear wall I02 of the gear box, as by bolts I23, and the sleeve I22 is ,-jour naled in an anti-friction bearing I24 .carriedby a member I25 rigidly secured to the rear wall 53 of the main frame, as by bolts I26, By making the axis of the drive shaft Il -3 coincident with the pivotal axis of the gear box Ill-I, the drive connection for the shaft I 13 is facilitated.

To swing the gear box .IilI about its axis to effect a feeding movement of the cutter, cam means is provided which is herein illustrated as acam member I (see Figs. 5, 6 and 8). The cam member 1.35 has a peripheral cam surface gradually increasing from a low point, indicated at Itl (see Fig. 5i, around the cam to a high point, indicated at 132, and then abruptly back to the low point -I3I. The peripheral cam sunface of the cam member 13G .coacts with a roller I53 mounted in a pivoted support 34. The support I343 is pivotally supported by means of a shaft I .J'ournaled in a sleeve 436 rigidly secured to the front wall .52 of the main frame, as by bolts I311.

The cam member I33 is power driven and rotates .in a clockwise direction, as viewed in .5, and the weight of the left-hand end of the gear box as viewed in. that figure is carried by the cam member resting on the roller 133.. As the cam rotates in the clockwise direction. the peripheral cam surface gradually lifts th left end of the gear box. swinging it about the pivotal axis of the drive shaft H3 and causing the cutter 29, which is positioned more or less directly above the pivotal axis H3, to move toward the right in cutting engagement with the work until a cut of the desired depth is made,

such depth being determined by the rise of the cam member H3 from .the low point 43] to the high point I32.

When the high point 1.32 of the cam member I33 passes over the roller I33 and beyond the dead center position, there is a camming action, due to the weight of the gear box on the roller I33, tending to swing the pivoted support 134 clockwise about the axis of .its shaft I35. Such swinging movement will be limited by a hat sur face MI! formed on the pivoted support I34 and adapted to engage the base 53. When the pivoted support I34 has been swung in this manner, the roller I33 will be moved out of the way of the cam member 139 and the gear box is permitted to fall by swin ing about the drive shaft H3 until the lower edge .of the front wall IO'I contacts a flattened surface ,MI .(see Fig. 5) formed on a stop member I42 rotatably mounted in the front wall 52 of the main frame. The stop member I42 is provided with a handle I43 by which the .stop member may be manually rotated. When the gear box .IIlll drops into contact with the flat surface I4I on the sto member [42 and the roller I33 has been moved away from the cam member I39 by the swinging move ment of the pivoted support I34, the cam member remains out of engagement with the roller I33 and will produce no further feeding movement .until the parts are returned to operative position.

To return the parts to such position, the shaft I35 is rotated by a knob I44 secured to the outer points thereof, a large force would have to be exerted on the knob I04 to shift the roller I33 into operative position and the cutter would immediately be shifted to a position corresponding to the point of contact, To avoid the necessity of exerting such a force and to insure starting the feed at the proper point, the knob I44 is turned sufficiently to bring the roller I33 into light contact with the cam surface without moving the roller fully into operative position. The roller is then held in such contact until the high point I32 of the cam passes the roller. The roller then may be easily turned into operative position adjacent the low point I3I since the stop member I42 holds the gear box in such position that there is a slight clearance between the low point of the cam and the roller. Rotation of the cam thereupon causes the cam surface to contact the roller because of the rise of the cam, and as soon as such contact is made, feeding of the cutter is started. During contact between the cam and the roller, the pivoted support I34 is held in operative position with the surface I45 in contact with the base 50 because of the direction of rotation of the cam. Such position of the cam roller is determined by a flattened surface I45 formed on the pivoted support I 34 and adapted to engage the base 50 when the cam roller I33 is in operative position. Thus, the cutter will be fed into the work by the action of the cam member I30 toform a cut of the desired depth and upon completion of such cut, the feeding movement is stopped and is rendered inoperable untilthe roller I33 and the cam member I30 are again placed in operative position to each other through use of the handle I43 on the stop member I42 and the knob I 44 for turning the'pivotal support I34'of the roller I33. i

Since the end of the tool post 35, which has the cutter 29 secured thereto, closely approaches the indexing disk I2 and the clamping disk I3 at the end of a cut, as is apparent in Fig.3, the slide 60 must be carefully adjusted to prevent the tool post from contacting the indexing disk and clamping disk. To assist in such adjustment, the stop member I42 at its side opposite the flattened side MI is provided with a flattened surface I 46 which hold the gear box and consequently the cutter 29 in the position they occupy at the end of the cut. Manual rotation of the hand lever I42 by its camming action on the gear box will lift the gear box about its pivot and when the flattened surface I43 is in contact with the gear box, the cutter 29 is held in the same position as at the end of the cut. The slide 60 may then be adjusted to provide suitable clearance between the tool post and the indexing and clamping disks.

The cam member I30 is adapted to be power driven, as heretofore mentioned, and is preferably driven from the same source of power as the cutter 20. The means for driving the cam member I30 thus is connected to the cutter drive and, in the present instance, the shaft III carrying the idler gear IIO, which is part of the cutter drive, is provided with a pinion I50 meshing with a large idler gear I5! (see Figs. 5 and 8) keyed on a stub shaft I52 journaled in the front and rear walls I0! and I32 of the gear box. The stub shaft I52 also carries a pinion I53 meshing with a gear I54 keyed to a shaft journaled in the front and rear walls IOI and I02 of the gear box. The shaft I 55 projects through the front wall I0! of the gear box and carries the cam member I30 on its front end. Thus, the cam member I30 is driven from the same source of power as the cam member 40 which operates the cutter 29, and the correct relation between the cutter speed, that is, the rotative' movement of the cutter during rocking, and the rate of feed can thus be obtained, as well as synchronizing the cutter movements with the feed.

In operation, the work piece is clamped in the work holder 51 and the indexing lever TI is engaged in one of the notches in the indexing disk I2. The indexing disk is also clamped at this time to the slide 30 by means of the nut 80. The slide 60, of course, is adjusted longitudinally to hold the Work piece in proper relation to the cutter 29.

The main drive shaft H3 is then driven and, assuming that the cam member I30 is in operative relation with the roller I33, the drive causes rotation of the cam member I30 to swing the gear box I00 clockwise, as viewed in Fig. 5, about the axis of the drive shaft I I3 to move the cutter 29 toward the work.

Operation of the drive shaft I I3 also causes rotation of the cam member 40 which, through its peripheral cam surface in contact with the roller 36 on the tool post 35, causes the cutter to be reciprocated toward and from the work while simultaneously being fed in that direction. The action of the cam member '40 on the roller 36 actually causes the arm 90 to swing about its pivotal support 9| but, since the movement effected by the cam is so slight, the resultant movement of the cutter caused thereby may be said to be reciprocatory in character. At the same time, rotation of the cam member 40 causes a swinging movement of the lever 37 secured to the tool post 35 and the cutter is rocked back and forth about its axis 3|. Thus, the cutter is moved into the work a few thousandths of an inch by the reciprocatory -movement effected by the cam member 40 at the same time that it is swung through a cutting stroke due to the rocking movement of the cutter. On the-return stroke of the cutter, the latter is swung away from the work so that the cutter clears the work during such movement. Furthermore, the gear box is gradually swung by the cam member I30 so that the cutter is moved inwardly relative to the work in addition to the reciprocatory movement imparted thereto.

When the cutter has been fed inwardly relatively to the work to the desired extent, that is, when the cam member I30 has made on rotation from the low point I3I to the high point I32, the latter exerts a camming action on the roller I33 to swing the pivotal support I34 about its supporting shaft I35. The roller I33 is then moved out of the way of the cam member I30 to render the feed inoperative, and the gear box I00 swings downwardly to rest on the flat surface I4l of the stop member I42.

The clamping nut on the work support 51 is then loosened and the indexing lever I1 is swung to remove its tooth from the notch in the indexing disk. The indexing disk is rotated suflisateen cientl-y to bring the. next notch into position for engagement by the tooth on the indexing lever and the nut 86 is retightened to clamp the work piece in the new position to permit the cutter to out another slot in the work piece. The knob. M4 is then turned in the manner heretofore described to bring the pivoted support l-34- for the roller I33 back into operative. position. The feedin mechanism is thereby rendered operative and the cutter is fed into the work to out another notch therein. This is repeated until all the notches are completed in the work piece, and at that point the work piece is removed fromthework holder.

By the combinedreciprocatory. and rocking movement of the cutter, together with the feeding movement imparted thereto, a slot willbecut in the ring in which the ends. of each slot are generally radial. of the. ring and, consequently, the angular extent of the slot at the outer periphery is substantially the same as the angular slot at the inner periphery. This results in a. ringhavingv a number of advantages as heretofore described.

Iclaim:

1. A- slotting machine comprising a cutter having a series; of teeth arranged in an are about an axis, and means rotatably supporting said cutter. on said'axis, said means being shiftable bodily in a directionperpendicular-to said axis, and mechanism for rocking said cutter and simultaneously shifting said, means.

2. A. slotting machine. comprising a, cutter having a. series ofteeth arrangedin an. are about anaxis,, and means rotatably supporting said cutter on said axis, said. means being movable bodily perpendicularly to. said: axisand mechanism for rocking saidcutter about said axis in one direction. and for moving said means bodily toward and from thework during rocking in said. onedirection and then for rocking said cutter the opposite direction and. for moving said means bodily farther from the: work and back towardthe. work during rocking in said opposite direction.

3, Aslotting machine comprising-a cutter having aseries of teeth arranged in an arc aboutan axis and. having a portion. extending on the opposite side of said axis from. said. teetlu a, cutter support, having said. portion secured thereto, a member rotatably carrying said cutter support for rocking movement. about said axis, andmounted, for shifting movement toshift. said cut.- ter, and rotatable, means for rocking, said cutter support, and for shifting, said, member tosimultaneously rock. and shiftsaid cutter...

4,. A slotting. machinecomprising an elongated cutter having, a seriesof teeth formed on one end about an axis located adjacent said end, a cutter support having the other. end. of. said cutter secure d thereto, said cutter supportbeing mounted for rocking movement. about, said. axis, and for. reciprocating movement, perpendicular to, said axis, and a rotatable member having rocking means thereonfor efiecting said rocking movement ofsaid cutter support and reciprocating means, thereon for effecting said reciprocating movement of said cutter support to simultaneous- 1y. rock said. cutter relative tothe. Work. andto shift said cutter toward and. from the work.

5.. A. slotting machine comprising: an elongated cutter having a series 01 teeth formed on one end about anaxis located adjacent said end, a. cut..- ter support having the other end of, said. cutter secured thereto, saidcutter support being mount- 1.2. ed for rocking movement about. said axis and for reciprocating movement perpendicular to. said axis, and a rotatably driven cam disk havinga crank connection with said cutter support for imparting rocking movement to the latter andacam surface for imparting reciprocating movement to. the cutter support to simultaneously rock said. cutter relative to the work and to shift said cutter toward and fromthe work.

6. A slotting machine comprising an elongated cutter having a series of teeth formed on. one; end about. an axis located adjacent said end, a. cutter support having the other end of said out.- ter secured thereto, said. cutter support. beingv mounted for rocking movement about said axis and for reciprocating movement. perpendicular to said axis, a lever carried by said cutter sup-- port, and a. rotatably driven cam disk having a, peripheral; cam surface engaging said cutter sup.- port for reciprocating the. latter and having a. crank pin engaging. said lever for rocking the cutter support, whereby said cutter is simultaneously rocked relative to. the work. and. is. shiited toward. andfromthework.

7 A slotting machine comprising an elongated cutter having; aseries of teeth formed onone end. about. an axis. located. adjacent said end a cutter support, having the other end of said cutter se-- cured thereto, said cutter support. being mounted for rocking movement about. said axis and for reciprocating movement perpendicular to. said axis, a roller mounted: on. said. cutter support. a. lever carried by said cutterv support, and having a slot in its free. end, and arotatablv driven cam disk having a. peripheral cam. surface engaging, said roller. for reciprocating the cutter support. and having. a crankpin on one face, operating in said slotv for rocking the cutter support, where.- by said, cutter is simultaneously rocked relative. to, the work and is shiited'. toward and. from the Work,.

8, A, slotting machine comprising, an. elongated. cutter having an arcuately arranged series, of angularly spaced teethiormedon one end about. an axis locatecliadjacentv said, end, a. cutter sup.- port having the, other end of? said cutter secured thereto, said cutter support being mounted, for rocking movement. about said axisandfbr reciplocating movement perpendicular to. said axis, and; rotatably driven. cammeans for. reciprocating said cutter, support and. having a crank con.- nection. therewith for rocking the cutter support to. simultaneouslg rock the: cutter relative to the work and; to;.-reciprocate.-it toward and from the work, thev angular extent. of. the rockingmove.- ment beingv greater than the angle between the teeth whereby the teeth will clear; the work at. the endiofitherocking movement.

9;. A; slotting machine comprising an; elongated cutter having an: arcuatelyarranged series: or angularly: spaced teeth formed on one endabout an axis located adjacent said end; a cutter support having the" other" end of said cutter-secured thereto; saidcuttersupport being mounted for rocking movement about; said axis and forreciprocatingmovement perpendicular to said axis, said rocking movement. effecting a cutting stroke of the cutter anda return stroke, and a rotatably drivencombined cam and" crank means for simultaneously' rocking and" reciprocating. said cutter support, said;combined cam and crank means be.- ing; arranged to move the, cutter from an initial position toward the work and back to saidiinitial position during said cutting stroke and from said 'initial position away from the work and back to said initial position during said return stroke.

10. A slotting machine comprising a cutting tool having anlarcuately arranged series of teeth formed on one end thereof about an axis adjacent said end, a cutter support comprising a tool post having the other end of the tool secured thereto and an arm rotatably supporting said tool post on such axis and pivotally mounted on an axis spaced from the first-mentioned axis, and rotatably driven cam means for swinging said tool post in said arm to rock the tool about the axis of its teeth and for swinging the tool post and arm about the pivotal axis of the latter, to reciprocate the tool toward and fromv the work.

11. A slotting machine comprising a cutting tool having an arcuately arranged series of teeth formed on one end thereof about an axis adjacent said end, a cutter support comprising a tool post having an offset portion with the other end of the tool secured thereto, and an arm rotatably supporting said tool post on said axis whereby the tool is supported for rocking movement about the axis of the teeth, said arm being pivotally mounted on an axis spaced from the first-mentioned axis whereby the tool is supported for reciprocating movement toward and from the work, and'combined cam and crank means for rocking said tool post in said arm and for pivoting said tool post and arm about the axis of the latter.

12. A slotting machine comprising a cutting tool having a series of teeth arranged in an are about an axis located at one end of the tool, a cutter support comprising a tool post having an offset portion at one end to which the other end of the tool is secured, and an arm rotatably supporting said tool post intermediate its ends on said axis, said arm being pivotally mounted on an axis spaced from the first-mentioned axis, said tool post having a roller and a lever mounted on the other end thereof, and a rotatably driven cam member having a peripheral cam surface engaging said roller for pivoting said arm about its pivotal axis and thereby reciprocating the tool toward and from the work and having a crank pin engaging said lever for rocking said tool post and thereby rocking the tool about the axis of its teeth.

13. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post rotatably mounted on said arm, a cutter carried by said tool post, combined cam and crank means carried by said gear box for rocking said tool post to rock the cutter relative to the work and for swinging said arm to reciprocate the cutter toward and from the Work, and feeding means carried by said gear box for swinging the latter to feed the cutter into the work.

14. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post rotatably mounted on said arm, a cutter carried by said tool post, combined cam and crank means carried by said gear box for rocking said tool post to rock the cutter relative to the work and for swinging said arm to reciprocate the cutter toward and from the work, feeding means carried by said gear box for swinging the latter to feed the cutter into the work, and drive gearing carried by said gear box for 14 driving said cam and crank means and said feeding means.

15. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post rotatably mounted on said arm, a. cutter carried by said tool post, combined cam and crank means carried by said gear box for rocking said tool post to rock the cutter relative to the Work and for swinging said arm to reciprocate the cutter toward and from the work, feeding means carried by said gear box for swinging the latter to feed the cutter into the work, a drive shaft mounted in said main frame and comprising the pivotal support for said gear box, gearing mounted in said gear box and connecting said cam and crank means with said drive shaft, and gearing mounted in said gear box and connecting said feeding means with said driveshaft.

16. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post mounted on said arm and carrying a roller and a lever, a cutter mounted on said tool post, a rotatably driven cam member carried by said gear box and having a peripheral cam surface engaging said roller for swinging said arm to reciprocate, the cutter toward and from the work, said cam member having a crank pin engaging said lever for imparting rocking movement to said tool post to rock the cutter relative to the work, feeding means carried by said gear box for swinging the latter to feed the cutter into the work, and means mounted on said gear box and engaging said arm for holding said roller in engagement with said cam surface with substantially uniform pressure throughout the feeding movement.

17. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post rotatably mounted on said arm, a cutter carried by said tool post, combined cam and crank means carried by said gear box for rocking said tool post to rork the cutter relative to the work and for swinging said arm to reciprocate the cutter toward and from the work, and feeding means for swinging the gear box to feed the cutter into the work, said feeding means comprising a rotatably driven cam carried by said gear box, and a roller engaging said cam and carried by said main frame.

18. A slotting machine comprising a main frame, a work support mounted on said main frame, a gear box pivotally mounted in said main frame, an arm pivotally mounted on said gear box, a tool post rotatably mounted on said arm, a cutter carried by said tool post, combined cam and crank means carried by said gear box for rocking said tool post to rock the cutter relative to the work and for swinging said arm to reciprocate the cutter toward and from the work, and feeding means for swinging the gear box to feed the cutter into the work, said feeding means comprising a rotatably driven cam having a peripheral cam surface gradually increasing from a low point around the cam to a high point and abruptly back to the low point, a roller engaging said cam; a pivoted support mounted on the main frame and carrying said roller, the high point on said cam being adapted as it passes said roller to swing the pivoted support to an out-of-the-way animus:

1'5 to preventreeengagement of saidi cm with the roller, and stop means for hokdmg saidi gear box an. inoperative position when said pivoted support. is: swung to: its out-of-the 'way position.

IQ. A slotting machine! comprising: a frame; a work support. mounted on said main; frame; a. gear box pix/ otally mountiedi frame, cutta'er supporting means. carried by said gear box; a cutter carried by said means, dmive means carried by s'aidi gear box for animating said cutter supporting means; feeding: means: for magma said gear box to: feed the cutter into the work; said feeding means including a cam, means for ammo said cam, a rollen coasting with said cam, amzE a pivoted suppontmounted on said main frame and carrying said roller, said being adapfied" to swing said pivoted support; to an: out-- of-iihe-way positionat the end 011 the: feeding movement; to hold the roller out of engagement with the cam, stop means for supporting said gear box when said rol'ler is out oi engagement with the cam, and manually openablea means connecked to said pivoted support for swinging the latter to its operative position to reengage said rol-ier'wiifli said cam when the cam is so positioned reiafiive to the roller as toinitiate tori-111 feeding movement;

20. A slotting: machine comprising a; frame, 8: work support adjustabl'y' mounted on 16 said: main frame; a. gear box. piwomliist' in said; main. frame,v cutter supporting means can-- riedz by said; gear box, a cutter by said means in spaced tn the; pivotal axis of; thegean box; drive; means. carried by said gear boas for actuating: said cutter supporting; meat-Izmi feeding for swinging; said: gear box about. its pivotal axis to teed; the cutterinto the work, means mmmted on said mainv frame: and manually shiftable i'nxo engagement; with said; gear box supporting: said: gear box in a: posi:-- corresponding: to the position it occupies; at the end: of. swinging; moyement for feeding: the cutteir into a work, whereby said gearbox may be held. in posiiiion: and said work support may be adjusted in relation to the position of'tzhe cutter at; the end of; its: feeding movement.

Number Name Date.

531,317 i Jan. 1;, I895 1,028,125 Melling June. 4, 1 912 1 ,285,66'F Fredman Nov. 26, I918 FOREIGN PATENTS Number Country Date- IT,6&(E 23-3, 1898' 

